Field of the Invention
This invention relates generally to the machining and, more particularly, to micromachining processing of workpieces.
Discussion of Related Art
Micromachining generally refers to the process of creating and/or modifying micro-features on a workpiece through the removal of material from the workpiece.
Micromachining through the use of a laser is a common micromachining technique. Laser micromachining technology affords numerous advantages, including good flexibility (due to the ease of controlling and varying of laser spot scanning trajectory), non-contact (where the primary machining tool, which is the laser beam, does not mechanically contact the workpiece), and high spatial resolution (down to less than 10 microns). Consequently, laser micromachining has many current and potential applications, such as including, but not necessarily limited to, creating micro-features for medical devices and solar cells, and surface texturing of mechanical parts to enhance their tribological properties, for example.
Unfortunately, current forms of laser micromachining may often suffer from one or more of the following drawbacks:
(i) debris deposition,
(ii) laser-induced harmful residual thermal effects (which may include surface oxidation layer, recast layer, heat affected zone, cracks, etc.), and
(iii) harmful surface tensile residual stresses (which may weaken the mechanical properties of the workpiece), and which may also be regarded as a type of laser-induced harmful residual thermal effect.
The above-identified drawbacks may often be more difficult, expensive, and/or time-consuming to minimize, avoid or completely remove than is desired or preferred.
Thus, there is a need and a demand for techniques or processes and associated systems for micromachining whereby various of the above-identified advantages of laser micromachining can be realized while simultaneously avoiding or minimizing one, two or all three of the above-identified drawbacks that may be associated with conventional laser micromachining.